NFPA 99 actually acknowledges the metalic raceway being the better EGC.
Roger
Skeshesh, I am looking at the 2002 and it is A.4.3.3.1.3.May I ask for a reference Roger?
NFPA 99 A 4.3.3.1.3
The performance of the grounding system is made effective through the existence of the green grounding wire, the metal raceway, and all of the other building metal. Measurements have shown that it is the metal raceway and building steel that provide most of the effective grounding path of less than 10 milliohms at the receptacle, including plug to receptacle impedance. The green grounding wire becomes a backup, not a primary path performer.
Skeshesh, here is what it says
Roger
Interesting, thank you Roger. I haven't the time to look it up right now so thanks for the reference. I'll need to dig deep into 99 soon though as there's a big project with a VA hospital coming up soon.
Also the new requirement that there be a grounding conductor installed in emt outdoors in the 2011